Cables for Kenwood TM-D710

The pinout of the data port in this transceiver is the same as in Yaesu FT-8xx series so same cables can be used (** see below) .

For serial CAT control, Digirig should be in RS-232 configuration.

Manual can be found here.

:warning: ** The cable kit is now available in store:

Additional discussion here.

Cool! I know we talked about this before, but nice to see it confirmed. On my list to get those cables, but not high priority as my D710 is in my truck, and my 706 there is already configured to use Digirig for Winlink

Looking at my TM-D700, it looks like the same pinout for the DATA Terminal as the ones on the TM-D710 (connecting to the radio body), so the same cable should work with those radios as well. When I can get the cable, I’ll test both

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Did you ever test this?



I’m confused about the pinout for this DIGIRIG-SERIAL cable. The DIGIRIG-SERIAL diagram shows pin 3 is ground, but the Kenwood TM-D710 diagram (and manual) shows that pin 4 is ground in the mini-DIN8 connector. Is the DIGIRIG-SERIAL diagram is incorrect (for the Kenwood, anyway)? I don’t own this cable, but I am making my own version of it.

Yes, the serial cable from FT-8xx kit doesn’t match the pinout for TM-V71A/D710 models.
The correct kit for these transceivers is:

Thank you! I see there’s no wiring diagram on the order page like there is for the Yaesu cable. Can you point me to the wiring diagram for this cable?

The reason I’m curious is that Kenwood includes RTS/CTS pins in their mini-DIN8 connector. My experience using the Kenwood OEM serial cable is that those RTS/CTS pins are needed for CAT communication with the radio. Using the Kenwood serial cable with Flrig, for example, I can only get Flrig to communicate with the radio if I check the RTS/CTS box in Flrig. Of course, this isn’t going to work with the DigiRig because RTS is used for PTT in the audio connector. Is RTS connected to CTS on the mini-DIN8 cable end of the DigiRig serial cable?

:warning: [EDIT: this reply is incorrect, please see correction later in this thread]

Below is the pinout for that cable. And yes, the hardware flow control lines (RTS/CTS) are not connected and the RTS signal is used for PTT control. On some cables for older transceivers the RTS and CTS are connected (loopback), but I don’t think it is necessary here. Please let me know if you run into any difficulties with CAT control.

Thank you. I built the cable in your diagram and tested with Flrig 1.4.7 on Linux (RPi 4B Bullseye with latest updates ) and Windows 11 (with latest updates). I have both a Kenwood TM-D710G and a TM-V71A. I have a DigiRig 1.9 configured for RS232.

The serial cable as depicted in your diagram does not work for CAT control with either radio in either OS. However, if I loopback RTS to CTS on the Mini-DIN8 connector it works great with both radios and both OSs (CAT and PTT). In all cases, I had RTS/CTS unchecked in the Flrig Config > Setup Xcvr and RTS set to BOTH in Flrig Configure > PTT-Generic.

This is consistent with the behavior of the Kenwood OEM CAT cable. If I use the OEM cable and disable RTS/CTS in Flrig Config > Setup Xcvr, Flrig cannot communicate with the rig (710 and 71A). CAT works fine on both radios with the OEM cable when RTS/CTS is enabled in Flrig Config > Setup Xcvr.

So, it appears the RTS to CTS loopback is required.

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Thank you for the information.
When I’m back stateside, I’ll re-check to see I there is loopback in the store cables and will add it if it’s not there.

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Just to chime in here.

I have the cable set that K0TX provided and I can both use the connection from the head unit (TNC) to the Serial connection on the DigiRig, and the RadioBody DATA connection to the Audio port on the DigiRig. I can use the Serial connection for the TNC and the audio connection works for sending/receiving data, but I cannot do RigCTL with hamlib on any version to send CAT control changes.

It’s not been a big deal for me since I have the radio sitting right next to me and I can easily change the frequency, but it would definitely be nice to let the software do it for me.

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In order to use CAT control, the DIGIRIG-SERIAL cable must be connected to the PC port on the radio body (next to the DATA port).

Yup, I’m aware. I use the RS232 cable / Serial to the head for Packet. The challenge is essentially having the need for two serial connections, one to the head for packet and the other to the body for CAT control (PC Port). Then the third connection to the DATA port on the radio for the audio part of the transmission.

My challenge is that the PC Port / CAT doesn’t seem to work with the DigiRig on my Mac with hamlib. The rigctl/rigctld times out trying to control the radio. I’ve always assumed the problem was hamlib lacking the proper driver for the TM-D710.

I’m about to test the KP5 cable from RT Systems connected to the PC port and Hamlib to see if that works.

So, played with the setup again today. Here is my setup.

Back of Radio : PC port → RT Systems Cable (/dev/cu.usbserial-RTXXXXX) (This works with CAT commands through Hamlib (updated to the latest) and rigctl (igctl -m 2034 -r /dev/cu.usbserial-RTXXXX)
DATA Port → DigiRig + Kenwood cable from K0TX)
Back of Head : K0TX cable (modified for TM-D710 to do serial) to the Serial port on DigiRig) Works with the TNC.

My experience has been that when I use the DigiRig (Serial) to the back of the TM-D710 hamlib times out. When I use the RT systems cable, the connection is nearly instantaneous on all serial speeds tested. When I use the Serial port on the DigiRig to the Head unit for the TNC, it works as expected.

@Mark Interesting. I’m guessing your K0TX serial cable does not loop back RTS to CTS on the mini-DIN8 and so it does not work for CAT on the PC port (back of radio).

Yup, that’s my theory as well. Interesting that it works for the RS232 → TNC but not the back of the radio though.

Sorry to be a pain - so I just received my cables and digirig today and I am not sure what I am doing wrong, if anything. I have my cables connected to the back of the radio (PC and Data ports), and have D710 selected in FLDIGI for hamlib control. What settings in FLDIGI do I need to select for this to work? If I select RTS/CTS it goes into transmit mode immediately. Do I need a new cable (people are mentioning a loop back cable)? Any help / feedback would be great!

Just an update that I’ve gotten VARA FM working with Winlink but still no success with FLDIGI.

@K0TX sorry for jumping around threads - I’ll post here since this appears to be the issue that I’m having as well. I could not get FLDIGI to work using the provided serial cable. I remembered that I had a RT Systems cable and tried that with FLDIGI to confirm my settings were correct and it worked. I wouldn’t be as sad if it weren’t just CAT control that didn’t work - I can’t get the PTT to function in FLDIGI. It just doesn’t work at all, which is surprising since VARA PTT works. I would expect that the PTT would at least work using the com port / RTS just like VARA but it does not.

Packet radio using Soundmodem works, but can only get JS8 or WSJTX working in non cat mode (which is fine).

Let’s start with PTT. Please share the screenshots of your FlDigi configuration pertaining to CAT control and PTT. We’ll go over that.

Also you can confirm that the PTT hardware is working by doing this test: